I'm new here and just thinking about doing some small things to help out with fuel economy. I'll be looking around for ideas. Driving a 2012 Prius with 89K miles. Any advice for beginners is welcome. Thanks

There isn't a whole lot of simple mods you can do to a Prius to improve it's efficiency. It's already an efficient motor with a computer managing the hybrid system for maximum efficiency.

Inflating your tires to sidewall max should help. In my mom's '08 Prius, inflating the tires from 36 PSI to sidewall max of 50 PSI showed a tested improvement from 43.8 MPG to 47.6 MPG at highway speeds, with new winter tires, in semi-wintry conditions with temps hovering in the 30s F. Subsequent drives outside of testing have favored the theoretical 3 MPG improvement.

Strategic grille blocking helps the car warm up to it's optimal running temperature faster, but you would need to monitor coolant temperatures to ensure that you aren't blocking off too much of the grille.

Larger things would include pulse-n-glide driving, lighter wheels, skinnier tires, boat tail, etc., but those are generally considered to be more radical and expensive.